Most of what a devops person does is in fact development but it is of the non value adding variety. Basically a devops person spends the vast majority of their time configuring common off the shelf software, scripting this or that, etc.
A singular matrix is a matrix which has no inverse because its determinant is zero. If you recall, the inverse of a matrix is. 1/ ad-bc multiplied by: [ d -b ] [-c a ] If ad-bc = 0, then the inverse matrix would not exist because 1/0 is undefined, and hence it would be a singular matrix. E.g.
Matrix. A matrix is a collection of data elements arranged in a two-dimensional rectangular layout. The following is an example of a matrix with 2 rows and 3 columns. We reproduce a memory representation of the matrix in R with the matrix function. The data elements must be of the same basic type. + c(2, 4, 3, 1, 5, 7), # the data elements. + nrow=2, # number of rows. + ncol=3, # number of columns. + byrow = TRUE) # fill matrix by rows. [,1] [,2] [,3]. [1,] 2 4 3. [2,] 1 5 7. An element at the m row, n column of A can be accessed by the expression A[m, n] .